ACA-1233n

68030-based Accelerator Card for Amiga 1200

This accelerator comes with an 68030 processor (incl. MMU) in
gold/ceramic packaging and 128 MBytes of physical memory, 1 MByte
of which is being reserved for Kickstart re-mapping.

The ACA-1233n comes with a number of improvements over its predecessor
ACA-1233. Although clocked at
the same speed, performance has been improved in almost every aspect.

The ACA-1233 boards have much faster memory performance than any accelerator
before - especially with cache and burst enabled. That's because the burst
sequence is the fastest-possible sequence that the 68030 can perform: It's
a sequence of four 32-bit transfers in four CPU cycles, which has not been
shown before the introduction of the
ACA-1230 in 2010.
The result is outstanding performance, even in comparison with other
68030-based accelerators at higher clock rates.

The ACA-1233n is PCMCIA-friendly: It will not disable the PCMCIA slot, so you
can continue to use a networking card in that slot.

New Features

memory auto-configuration

dynamic clocking for power-saving

card enable/disable in software

memory available to onboard CPU if accelerator is switched off

faster clockport for RapidRoad yields a 55% speed increase

new software compatibility settings

improved A1200 compatibility

The memory of the ACA-1233n is auto-configuring. This means that all memory
is available from a power-up without installing any software on the computer.
The old ACAtune tool which was required for previous ACA cards is not required
any more.

If you do not require full speed, the card can be slowed down in order to save
power. The CPU governor program will monitor CPU requirements and adapt to the
demands of your application, resulting in the best power/performance ratio
for your use case.

Some software does not like accelerated execution. For these cases, the ACA-1233n
can be switched off in two steps: The first step is to switch off the 68030 CPU
and give control to the CPU of the host computer. On an A1200, you can still use
9 MBytes of fast memory, which are also auto-configuring. The second step
is to switch off additional memory as well, getting the computer into its stock
state. If used on an
ACA-500 or
ACA-500plus, memory can
not be used by the 68ec000 processor.

The clockport of the ACA-1233n can either take an
RTC module, or the
RapidRoad USB host controller.
Operation of RapidRoad is 55% faster than with the internal clock port of the A1200
computer. This function is available in all modes of operation on an A1200 computer and
on the ACA-500plus. It is not available
if the ACA-1233n is operated on an ACA-500.

If software is not compatible with 32-bit memory, Z3 autoconfig or a
newer Kickstart version, the ACA-1233n
allows downgrading to Z2 autoconfig, older Kickstart versions and also lets you switch
off the so-called "trapdoor memory area". The MapROM function is even available
on an A1200 if the 68030 CPU is switched off, which allows you to use different Kickstart
ROM versions without opening the computer and exchanging ROM chips.

Last but not least, the ACA-1233n features a new A1200 motherboard interface. Some A1200
mainboards have been delivered with the wrong timing components and require modification
for reliable use with accelerators. With the new improved interface, the ACA-1233n is
less likely to require these board patches. Although this has been tested extensively,
timing patches may still be required.

Package Contents

ACA-1233n accelerator card with RAM and CPU assembled

installation leaflet

In addition to that, you will need:

a transfer method for the ACAMapRom tool to your Amiga (free download from the
ACA-1233n Wiki)

motherboard patches as described by Commodore: A1200 capacitors E123C and E125C may need to be removed